JPS639733A - Fluid joint - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a fluid coupling equipped with a scoop pipe capable of scooping out working fluid to empty the inside thereof.

<Prior Art> This type of fluid coupling is disclosed in, for example, West German Patent No. 977.
．． No. 505. In such a fluid coupling, the working fluid flows into a toroidal working space defined by a vaned hub consisting of a first hub and a second hub, and a scoop pipe arranged along the working space. They are filled inside and out.

Generally, this scoop tube chamber is defined by a casing that rotates integrally with a first hub provided with vanes on the outside, and into which a non-rotating scoop tube through which a portion of the working fluid continuously flows out is generally radially directed. It has been extended to As described above, fluid couplings have been proposed in which the filling rate of the working fluid can be changed and the rotational speed and torque characteristics can be changed by providing a fixed or radially adjustable scoop pipe. Due to the back pressure of the working fluid acting at the inlet of the scoop tube, the evacuation of the working fluid from the scoop tube chamber and the conveyance of the working fluid to the following conduit is effected by an automatic control system. In this regard, it is important to maximize the uniformity of the flow of working fluid into the scoop tube. Otherwise, pressure fluctuations will occur throughout the line, interfering with subsequent automatic control systems. It has been found that if the velocity of the fluid rotating in the scoop tube chamber is maximally equal to the rotational speed of the rotating casing part, the flow of the working fluid to the inlet boat of the scoop tube will be uniform.

However, this objective has not been realized to a satisfactory extent as explained below.

A. In the conventional fluid coupling shown in FIG. 1 of DE 977.505, the scoop tube chamber is located behind the pump hub. That is, the scoop tube chamber is defined by the rear part of the pump hub and the part of the joint casing fixed to the pump hub, and all walls defining the scoop tube chamber rotate at the same speed. In this case, the effect that the working fluid in the scoop tube chamber rotates at approximately the same speed as the first hub and the joint casing is observed due to the combination with the vanes provided on the inner wall surface of the casing in the direction perpendicular to the axis. There is a structural disadvantage in that the joint casing must have a double structure. That is, not only does the first vaned hub have a joint casing secured to form the scoop tube chamber as described above, but also
A joint casing surrounds the second winged hub. As a result, the manufacturing cost and weight increase, and therefore, it is considered that a fluid coupling having such a configuration is not suitable for practical use.

B. FIG. 2 of the above-mentioned West German patent no. It is shown. Such an arrangement has the advantage that only one joint casing is required. However, it is fortunate that the walls defining the scoop tube chamber rotate at different speeds. This is because, as is well known, the second vaned hub rotates at a somewhat slower speed than the joint casing secured to the first vaned hub even in continuous operation. Therefore, the working fluid in the scoop tube chamber is prevented from flowing in the circumferential direction more effectively than in the configuration shown in FIG. 1 of the above-mentioned West German patent specification.

In contrast, an attempt has been made to solve the above-mentioned inconvenience by providing vanes 23 for entraining the working fluid in the scoop tube chamber not only on the casing wall surface perpendicular to the axis but also on the casing wall surface parallel to the axis. Attempts are being made to do so. However, apart from making the manufacturing of the vanes more complex, these configuration changes do not effectively prevent the occurrence of pressure fluctuations in the pipe system downstream from the scoop pipe. There wasn't.

C1 An arrangement for dealing with such pressure fluctuations is disclosed in German Patent No. 764.378.

The fluid coupling has a scoop tube chamber defined by two casing walls fixed to the first vaned hub. In order to dampen or prevent pressure fluctuations, the scoop tube chamber has an internal structure formed in the form of ribs extending radially inwardly and parallel to the axis. However, this fluid coupling requires two coupling casings and has a rib-like internal structure, which makes the structure very complicated.

<The key points to be solved by the invention> Therefore, an object of the present invention is to provide a fluid coupling of the type described above, which suppresses pressure fluctuations in a scoop pipe and a pipeline system downstream from the scoop pipe. Another object of the present invention is to provide a fluid coupling having a simple structure and having a single casing that is connected to one coupling member and surrounds the other coupling member to form a scoop tube chamber.

<Means for solving the problems and their effects> The above purpose is to provide a radial adjustment area of the scoop pipe and a contact area with the working fluid on the fluid-side inner surface of the rotary joint casing defining the outside of the scoop pipe chamber. This is achieved by providing elongated recesses each extending beyond the . By providing such a groove-like recess, the working fluid comes into contact with a surface having arbitrarily formed irregularities. As a result, the working fluid can be reliably drawn in in the circumferential direction. It also has the effect of uniformizing the inflow of working fluid into the scoop pipe inlet boat. this is,
This is because the pressure fluctuations occurring in the current scoop pipe can be suppressed to at least a considerable extent.

It is also a significant improvement compared to the prior art fluid coupling shown in FIG. 2 of the above-mentioned German Patent No. 977.505. By providing the blades of the joint on the casing wall in the direction perpendicular to the axis,
It is believed that the working fluid flows radially outward, which causes pressure fluctuations. On the other hand, if the joint has a large number of relatively narrow groove-like recesses, it is believed that the irregular flow of the working fluid in the lateral direction is completely suppressed. Furthermore, the difference in rotational speed between one of the casing walls and the rear part of the vaned hub located inside thereof, which has been considered disadvantageous in the past, is not considered to cause any particular problem. In this way, the problems of the prior art are solved and the well-known simple structure fluid coupling using one coupling casing is put into practical use.

Another important and fundamental feature of the invention is the large number of groove-like recesses formed in the inner wall surface of the scoop tube chamber. When a fluid coupling having a scoop tube chamber with an inner diameter of 420 m was tested, pressure fluctuations could be almost completely suppressed using, for example, 137 grooves with a width of about 4 mm and a radial length of about 100 mm.

If the recesses are arranged uniformly and densely on the inner surface of the rotating joint casing, there is an advantage in that the working fluid can be entrained more effectively, especially by arranging the recesses in a radial direction. Furthermore, even when radial recesses are selectively arranged in a part of the rotating joint casing, that is, in a part of the wall of the rotating casing, entrainment of the working fluid and pressure fluctuation can be sufficiently and reliably suppressed. It has been confirmed that you can get it. Such a casing wall is preferably an outer casing wall of the scoop tube chamber or a partition between the scoop tube and one of the coupling members.

In order to prevent pressure fluctuations from occurring due to interference between rotating parts and the casing, the number of four parts is, for example, 137 as mentioned above.
It is better to use a prime number such as .

<Example> Hereinafter, an example of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a first joint member 1 connected to a prime mover (not shown) and a second joint member 2 for driving a load (not shown). A joint casing 3 is fitted around the second joint part 2 and connected to the first joint part 1 . This joint casing 3 defines a scoop tube chamber 4 behind the second joint part 2 . This scoop tube chamber forms an annular oil layer which rotates during operation of the fluid coupling, the width of which is determined by the scoop tube 5 arranged in the radial direction and which continuously scoops up the working fluid.

In order for the rotating annular oil layer in the scoop tube chamber 4 to scoop up the working fluid most effectively, it is necessary that the working fluid moves at a speed as close as possible to the speed of the casing 3. According to the invention, grooves 7 extending in the radial direction are provided on the inner surface 6 of the case sink 3 rotating on the drive side. The grooves 7 are holes for regularly increasing the unevenness of the surface 6.

On the other hand, a strong pumping action in the radial direction can be prevented by the simple configuration of forming the radial grooves 7. Otherwise, the working fluid in the annular oil layer will naturally move irregularly, resulting in lateral flow, making it difficult to control the working fluid to be scooped out effectively and uniformly.

The completely radial arrangement of the grooves 7 allows the working fluid to be moved generally tangentially towards the scoop tube.

In FIG. 2, the inner surface of the joint casing 3 is shown. As can be seen, the radial grooves 7 are arranged close to each other and extend radially from the inside to the outside of the joint casing 3. It has been found that it is advantageous to set the ratio of the width a of the groove 7 to the maximum inner diameter R of the scoop tube chamber 4 within the range of 1/40 to 1/60. Furthermore, it is more convenient to make the distance C between each groove at the inner end in the radial direction substantially equal to the width a of the groove 7.

FIG. 3 shows a cross-sectional view of the radial grooves 7. The cross section of the groove 7 can be rectangular, semicircular, or wedge-shaped. The depth and width of the single groove 7 are approximately several meters,
It is important that the edges transitioning from the smooth surface 6 to the respective grooves 7 are formed with relatively sharp corners.

<Effects of the Invention> According to the present invention, by providing the grooves, it is possible to suppress the radially outward pumping action to a minimum, and to effectively entrain the working fluid in the circumferential direction. pressure fluctuations can be reliably suppressed.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of the fluid coupling. FIG. 2 is a plan view showing the inner surface of a joint casing having grooves according to the present invention. FIG. 3 is a sectional view showing an embodiment of the groove. 1... 111th hand member 2... 2nd m hand member 3.
...Joint gauging 4...Dip tube chamber 5...Dip pipe 6...Surface 7...Groove

Claims (5)

[Claims] (1) Two bladed joint members that define a toroidal operating circuit, a joint casing that is coupled to one of the joint members and surrounds the other joint member, and a rotating casing and the other joint member. A fluid coupling comprising a non-rotating scoop tube disposed in a scoop tube chamber formed between the coupling member and the filling rate during operation is determined by the arrangement of an inlet port of the scoop tube, the fluid coupling comprising: A plurality of elongated recesses in the shape of radial grooves extending to the vicinity of the outermost radial direction of the scoop tube chamber are provided evenly around the periphery of the joint casing that rotates integrally with the one joint member. Features fluid coupling. (2) The ratio of the width of the recess to the distance at the radially inner end of the recess is approximately 1, and the ratio of the width of the recess to the maximum inner diameter of the scoop tube chamber is 1/40 to 1.
2. The fluid coupling according to claim 1, wherein the fluid coupling has a diameter of /60. (3) The recess extends radially beyond a radius corresponding to the adjustable area of the inlet port of the scoop tube. Fluid coupling as described. (4) The fluid coupling according to any one of claims 1 to 3, wherein the number of the recesses is a prime number. (5) The fluid coupling according to any one of claims 1 to 4, wherein a transition portion from the inner surface of the joint casing to the recess is formed with a relatively sharp corner. .